I think the Elixir DateTime API is really clean and well designed. The key was letting libraries explore the problem and surface the right interface, before bak

I think the Elixir DateTime API is really clean and well designed. The key was letting libraries explore the problem and surface the right interface, before baking it into the standard library. It does mean it took a long time for this to land but I'd say it was worth it. Learning from the failures of others also certainly helped.